Sheet-metal-working press



Oct. 30, 1928.

' F. J. RODE SHEET METAL WORKING PRESS s Shaw-Sheet 1 Filed June 2, 1927 Oct. 30, 192& I 1,689,500

F. J. RODE srmm' METAL WORKING PRESS Filed June 2, 1927 3 Sheets-Sheet F.' J. RODE SHEET METAL WORKING PRESS Filed June 2, 1927 3 Sheets-Sheet If Patented Get. 30, 1928.

"UNITED STATES PATENT "OFFICE- IREDRICH J, RODE, OF CHICAGO, ILLINOIS, ASSIGNQR 'IO MARQUETTE TOOL & MFG. COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION ILLINOIS.

.SHEET-METAL-WOBKING rnnss.

Application filed J'une2, 1927. Serial No. 195 895.

This invention relates in general to immovements in sheet metal working presses, but more particularly the invention has reference to aresiliently yielding bed or bolster plate for the press, and uponwhich plate one of the .co-operating dies for shaping the :material is mounted.

It is well knownthat sheet metal varies considerable in thickness and in working with material of this character upon a press it is necessary to set the press to accommodate the gauge of material to be operated upon. This is accomplished by adjusting the ram so that it will have a predetermined or set throw and during its descending movement and during its operation upon the work considerable stress is exerted upon the bed or bolster plate of the press.

It has been found that even in supplies of sheets sorted particularly to gauge there will be aconsiderable variance of thickness in some of the sheets.

It is therefore mani'festthat if the ram is set for a predeterminedthrow, should asheet of material .be inserted in the press to be operated upon by the ram when it descends, the bed of the press will be strained should it so happen that the. material is of a slightly greater thickness than the thickness to which the throw of the ram is set. Such occur- .rences seriously strain the bed "or bolster plate and oftentimes 'theorank shaft, which results in considerable damage.

. It isone of the objects of the present invention to overcome these difficulties and objections and to provide. a resiliently I yield ing bed or bolster plate which is adapted to :be set ata predetermined resistance pressure so that after 'the press has been .set so that the ram will have a predetermined throw, should .a sheet ofmateri-al ofa greater thickness than the thickness of the material \for which the press has been set, be inserted in the press the press will not be injured when the ram operates, by reasonof the fact that the excess pressure caused by the operationiof the ram uponuthe increased thickness of the work will cause the bed or bolster plate to yield.

Afterthe. material. of excess thickness 'has been operated upon the bedor bolster plate will assume its normal position.

A. further.:.object.-of the invention is to provide improved means .whereby :the irpre action press having a bolster plate constructed in accordance with the principlesof this invention applied thereto, parts being in section and parts broken away.

Figure 2 is a .right hand end elevation. of Figure =1, with parts broken away and parts in section.

Figure 3 is a horizontal sectional view taken. on line 3-3, Figure 1.

Referring more particularly to the drawing the numeral 10 designates the bed of the press, 11 the uprights, 12 a reciprocating ram which is connected by means of Ili-nks 13 with a crank shaft l i. Secured to the ram 12is a die 15 which co-operates with 'a die "16, and between which dies the work 17 :is placed.

Mounted upon the bed of the press is a bolster plate which preferably consists of a member #18 secured in any suitable manner to the press. FIhis member is provided with a chamber 19 of any desired size and con figuration. A member 20 is provided which ,co-operates with the member "18, and a pertionQl ofthemember 20 is shaped to forma piston which extends into *the chamber 19 of the member18. Packingmaterial 22 is provided to form ,aifluid tight joint between the .pistonand 'cylinder elements of these two members, and the two members are connected together in any suitable manner and for relative movement preferably by means of bolts '23 which pass loosely through the member 18 and have threaded engagement with themember 20. "The heads 24 of the bolts 2-3 are seated and operate within =recesses 25 in the member 18.

The die 16 is secured" to and su p'ported'by the -=member 220 preferably by means of a supporting or anchoring member 26.

he cylinder or chamber -19 within the member '18 is .adapte'd to rbe supplied with any desired fluid pressure. In the present exempliflcation of this invention the fluid employed is preferably a liquid 26 contained within a receiver or tank 27. Leading from the receiverr27 is a pipe or conduit 28 which has communication with the cylinder through a branch pipe 29, the branch pipe being connected and having communication with the valve chamber 30 in which a valve 31 (preferably of the flap type) is arranged. The valve chamber 30 has communication with the cylinder, preferably through a T coupling 32 by means of a conduit 33. A pressure gauge 34 may be provided to indicate the amount of pressure of the fluid.

Connected also with the T coupling 32 is another valve casing 35 which also has communication with the pipe 28 as at 36 so that liquid from the receiver 27 will pass through the pipe 28, branch pipe 29, valve casing 30, past the valve 31 into the T coupling 32 and thence into the cylinder 19. Liquid will flow out of the cylinder 19 into the T coupling 32 and will be arrested in its movement through the branch pipe 29 by means of the valve 31. A valve 37 is arranged in the valve casing 35 for closing communication between the valve casing 35 and the T coupling 32, while the liquid is flowing into the cylinder 19. When the valve 37 is unseated liquid will flow through the valve casing 35, through the connection 36 back into the pipe 28 to be delivered into the receiver 27. A T head 38 is arranged in the receiver 27 so as to prevent splashing. A pressure control valve 39 and a pressure gauge 40 may be provided, if desired.

The valve 37 is set at a predetermined resistance pressure. That is it is so set that it requires a predetermined pressure upon the fluid in the cylinder 19 by the piston member 20 to unseat the valve. To that end there is provided a resilient element 41, preferably in the form of a coil spring arranged within a housing 42, one end of the spring is seated against a seat 43011 the valve stem 44. The other end of the spring rests against a seat 45 which is contacted with a screw 46 threaded into the end of the housing i2. By adjusting the screw 16 the stress or tension of the spring 41 may be varied and thereby the resistance pressure necessary to unseat the valve 37 may be varied. A look nut 47 may be provided for maintaining the screw 46 in its adjusted position.

In use the spring 41 is adjusted to the predetermined pressure which it is desired to exert upon the valve 37 for determining the pressure which it is necessary to exert upon the fluid in the cylinder 19 to unseat the valve. Liquid is then admitted from the receiver 27 into the cylinder 19 through the pipes 28 and 29, valve casing 30 and T coupling 32. This will elevate the piston member 20 and maintainthe same in its elevated position against a resiliently yielding predetermined pressure. This pressure is sufficient to hold the die member 16 against a yielding action under the operation of the ram when sheets of predetermined and uniform thickness are being operated upon.

When, however,a thicker sheet of material is placed upon the die 16 the increase in thickness will, when the ram 12 descends, cause a pressure to. be exerted upon the bed or bolster plate in excess of the fluid pressure in the cylinder 19, with the result that the piston member 20 of the bolster plate will yield. Immediately upon the removal of the material of excess thickness from the press the fluid pressure in the cushion 19 will cause the piston member 20 to assume its normal position and thereby automatically reposition the die 16 for the thickness of material to which the press has been set.

lVhile the preferred form of the invention has been herein shown and described, it is to be understood that various changes may be made in the details of construction and in the combination and arrangement of the several parts, within the scope of the claims, without departing from the spirit of this invention.

What is claimed as-new is 1. A press for drawing sheet metal and the like embodying a bed, a movable supporting member forming with said bed a piston and cylinder unit, a die anchored rigidly to said'supporting member, and a ram reciprocable with a set throw, said cylinder containing a fluid which resists the movement of the piston and the die that is connected therewith when the latter is subjected to the action of the co-operating die on the ram, the said fluid operating to return. the die on the first said movable mem her to its normal position if it should be moved against said resistance.

2. A press for drawing sheet metal and the like embodying a bed, a movable supporting member forming with said bed a piston and cylinder unit, a die anchored rigidly to said supporting member, a ram reciprocable with a set throw, said cylinder containing a fluid which resists the movement of the piston and the die that is connected therewith when the latter is subjected to the action of the co-operating die on the ram, the said fluid operating to return the die on the first said movable member to its normal position it it should be movedv against said resistance, and means for varying at will the resistance pressure of said fluid. I i i 3. A press for drawing sheet metal and the like embodying a bed, a movable sup porting member forming with said bed a piston and cylinder unit, a die anchored rigidly to said supporting member, a ram reciprocable With a set throw, said cylinder containing a fluid which resists the movement of the piston and the die that is connected therewith when the latter is subjected to the action of the co-operating die on the ram, the said fluid operating to return the die on the first said movable member to its normal position if it should be moved against said resistance, and means for limit ing the return movement of the die on the bed of the press.

4. A press for drawing sheet metal and the like embodying a bed, a movable supporting member forming with said bed a piston and cylinder unit, a die anchored rigidly to said supporting member, a ram reciprocable with a set throw, said cylinder containing a fluid which resists the movement oi the piston and thedie that is connected therewith when the latter is subjected to the action of the co-operating die on the ram, the said fluid operating to return the die on the first said movable member to its normal position if it should be moved against said resistance, and co-operating stops on the movable member carrying the die and the said bed respectively for limiting the return movement of the die on the bed of the press.

5. A press for drawing sheet metal and the like embodying a bed, a movable supporting member forming with said bed a piston and cylinder unit, a die anchored rigidly to said supporting member, a ram reciprocable with a set throw, said cylinder containing'a fluid which resists the movement of the piston and the die that is connected therewith when the latter is subjected ri 'idl to said su aortin member a ranr reciprocable with a set throw, said cylinder containing a fluid which resists the movement of the piston and the die that is connected therewith when the latter is subjected to the action of the co-operating die on the ram, the said fluid operating to return the die on the first said movable member to its normal position if it should be moved against said resistance, and a variable resistance pressure controlling valve operable at will for varying the predetermined pressure of the fluid.

In testimony whereof I have signed my name to this specification on this 16th day of May, A. D. 1927.

FREDRICH J. RODE. 

